Configurable vacuum system and method

ABSTRACT

An exemplary configurable vacuum system is provided for use in coating or plating that provides the capability and versatility to handle substrates of significantly different shapes and sizes. The configurable vacuum system includes a vacuum table assembly, a mechanical drive, an electrical feed through, a filament, and a vacuum chamber. The vacuum table assembly may include a support frame, a sliding means, such as a roller or rollers, an insulated surface, and a platform operable to rotate and support the substrate. The mechanical drive is operable to rotate the platform, the electrical feed through provides an electrical signal to the substrate, and the filament is positioned relative the substrate. The vacuum chamber includes a main opening, an internal volume, and a receiving means, such as a railing or member, operable to receive and support the vacuum table assembly within the internal volume of the vacuum chamber and through the sliding means of the vacuum table assembly.

RELATED APPLICATIONS

[0001] Pursuant to 35 U.S.C. §120, this continuation application claimspriority from, and hereby incorporates by reference for all purposes,copending U.S. patent application Ser. No. 09/578,166, entitledConfigurable Vacuum System and Method, naming Jerry D. Kidd, Craig D.Harrington, and Daniel N. Hopkins as joint inventors, filed May 22,2000, and now U.S. Pat. No. ______. This application does not claimpriority from but is related to U.S. patent application Ser. No.09/427,775, entitled System and Method for Plasma Plating, naming JerryD. Kidd, Craig D. Harrington, and Daniel N. Hopkins as joint inventors,filed Oct. 26, 1999; U.S. patent application Ser. No. 09/576,640,entitled Mobile Plating System and Method, naming Jerry D. Kidd, CraigD. Harrington, and Daniel N. Hopkins as joint inventors, filed May 22,2000, and now U.S. Pat. No. 6,503,379; U.S. Continuation patentapplication Ser. No. ______, entitled Mobile Plating System and Method,naming Jerry D. Kidd, Craig D. Harrington, and Daniel N. Hopkins asjoint inventors, filed Jan. 6, 2003; and U.S. Divisional patentapplication Ser. No. ______, entitled Mobile Plating System and Method,naming Jerry D. Kidd, Craig D. Harrington, and Daniel N. Hopkins asjoint inventors, filed Jan. 6, 2003.

TECHNICAL FIELD OF THE INVENTION

[0002] This invention relates in general to the field of vacuum systemsand deposition technology for plating and coating materials and moreparticularly to a configurable vacuum system and method.

BACKGROUND OF THE INVENTION

[0003] Deposition technologies for coating and plating materials anddeveloping engineered surfaces may include any of a variety ofdeposition technologies. These deposition technologies may include, forexample, vacuum deposition, physical vapor deposition (“PVD”), chemicalvapor deposition (“CVD”), sputtering, and ion plating.

[0004] Generally, all of these deposition technologies require a vacuumsystem with a platform for proper support and positioning of thesubstrate within a vacuum chamber to ensure that a desired plating isachieved. The platform may also be referred to as a table, turntable,base plate, and the like. The proper support, presentation, andpositioning of the substrate on or by the platform during plating iscritical to achieve a desired, repeatable, and successful plating.Often, the platform must provide rotational motion to the substrateduring plating to achieve a more uniform or desired coating or plating.

[0005] Unfortunately, substrates come in all shapes and sizes and often,a platform that is used in a vacuum chamber to support or rotate asubstrate during plating works well with one particular shape or type ofsubstrate, but poorly for another. Further, many vacuum chambers onlysupport one type of platform or table, and few, if any platformscontemplate substrates of significantly different shapes and sizes. Thissignificantly limits the effective use of expensive deposition andplating systems, including expensive vacuum chambers and platforms.

SUMMARY OF THE INVENTION

[0006] From the foregoing it may be appreciated that a need has arisenfor a configurable vacuum system and method for use in coating orplating that provides the capability to handle substrates ofsignificantly different shapes and sizes. In accordance with the presentinvention, a configurable vacuum system and method are provided thatsubstantially eliminate one or more of the disadvantages and problemsoutlined above.

[0007] According to an aspect of the present invention, a configurablevacuum system is provided that includes a vacuum table assembly, amechanical drive, an electrical feed through, a filament, and a vacuumchamber. The vacuum table assembly may include a support frame, asliding means, such as a roller or rollers, an insulated surface, and aplatform operable to rotate and support the substrate. The mechanicaldrive is operable to rotate the platform, the electrical feed throughprovides an electrical signal to the substrate, and the filament ispositioned relative the substrate. The vacuum chamber includes a mainopening, an internal volume, and a receiving means, such as a railing ormember, operable to receive and support the vacuum table assembly withinthe internal volume of the vacuum chamber and through the sliding meansof the vacuum table assembly.

[0008] The present invention provides a profusion of technicaladvantages that include the capability to use a vacuum system forplating, such as plasma plating, substrates of significantly differentshapes, sizes, and dimensions. This greatly increases the value of sucha vacuum system by providing the versatility to use the same system tocoat many different types of substrates.

[0009] Another technical advantage of the present invention includes thecapability to provide substrate rotation in different planes, such asrotation on a horizontal plane and on a vertical plane. This increasesthe versatility and usefulness of the vacuum system and vacuum tableassembly.

[0010] Another technical advantage of the present invention includes thecapability to efficiently plate or “shoot” first array of parts usingthe vacuum system of the present invention, and then to quickly andexpeditiously transition to plate or “shoot” a second array of parts,whether the parts are similar or different, or require differentplatforms for plating.

[0011] Other technical advantages are readily apparent to one skilled inthe art from the following figures, description, and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] For a more complete understanding of the present invention andthe advantages thereof, reference is now made to the following briefdescription, taken in connection with the accompanying drawings anddetailed description, wherein like reference numerals represent likeparts, in which:

[0013]FIG. 1 is a schematic diagram that illustrates a system for plasmaplating that can be used to plate materials, according to an embodimentof the present invention;

[0014]FIG. 2 is a top view of a vacuum chamber of a system for plasmaplating that illustrates one embodiment of a platform implemented as aturntable;

[0015]FIG. 3 is a side view that illustrates the formation anddispersion of a plasma around a filament to plasma plate a substrateaccording to an embodiment of the present invention;

[0016]FIG. 4 is a sectional view that illustrates a deposition layerthat includes a base layer, a transition layer, and a working layer;

[0017]FIG. 5 is a flowchart that illustrates a method for plasma platingaccording to an embodiment of the present invention;

[0018]FIG. 6 is a flowchart that illustrates a method for backsputteringusing the system of the present invention, according to an embodiment ofthe present invention;

[0019]FIG. 7 is a front view of a vacuum chamber for use in aconfigurable vacuum system according to one embodiment of the presentinvention;

[0020]FIG. 8 is a bottom view of a support frame of a vacuum tableassembly according to one embodiment of the present invention;

[0021]FIG. 9 is a bottom view of the support frame as shown andillustrated in FIG. 8 with the addition of a filament power connectorcoupled to the support frame;

[0022]FIG. 10 is a bottom view of the support frame as shown andillustrated in FIG. 8 with the addition of a mechanical drive coupled tothe support frame and an electrical feed through coupled to the supportframe according to an embodiment of the present invention;

[0023]FIG. 11 is a top view of an insulated surface positioned betweenthe support frame and two support members, as shown, of the vacuum tableassembly according to one embodiment of the present invention;

[0024]FIGS. 12a-b is a top and side view of the vacuum table assemblywith a platform implemented as a turntable and a filament positioned asdesired;

[0025]FIG. 13 is a top and side view of the vacuum table assembly with aplatform implemented with a double roller assembly;

[0026]FIGS. 14a-b is a top and side view of the vacuum table assemblywith a platform implemented as a single roller assembly;

[0027]FIGS. 15a-b is a top and side view of the vacuum table assemblywith a platform implemented as a conductive plate; and

[0028]FIG. 16 is a side view of the configurable vacuum system with thevacuum table assembly being loaded into the vacuum chamber using a cart.

DETAILED DESCRIPTION OF THE INVENTION

[0029] It should be understood at the outset that although an exemplaryimplementation of the present invention is illustrated below, thepresent invention may be implemented using any number of techniques,whether currently known or in existence. The present invention should inno way be limited to the exemplary implementations, drawings, andtechniques illustrated below, including the exemplary design andimplementation illustrated and described herein.

[0030] Initially, a system and method for plasma plating is described indetail below in connection with FIGS. 1-6 to illustrate a type ofdeposition technology that may be used with the configurable vacuumsystem and method of the present invention. Finally, an embodiment ofthe configurable vacuum system and method are described in detail inconnection with FIGS. 7-16 that implement, as an example, the plasmaplating system type of deposition technology detailed previously inconnection with FIGS. 1-6. It should be understood, however, that theconfigurable vacuum system and method of the present invention are notlimited to such deposition technology.

[0031]FIG. 1 is a schematic diagram that illustrates a system 10 forplasma plating that can be used to plate any of a variety of materials,according to an embodiment of the present invention. The system 10includes various equipment used to support the plasma plating of asubstrate 12 within a vacuum chamber 14. Once appropriate operatingparameters and conditions are achieved, a depositant provided in afilament 16 and a filament 18 may be evaporated or vaporized to form aplasma. The plasma will contain, generally, positively charged ions fromthe depositant and will be attracted to the substrate 12 where they willform a deposition layer. The plasma may be thought of as a cloud of ionsthat surround or are located near the substrate 12. The plasma willgenerally develop a dark region, near the closest surface of thesubstrate 12 from the filament 16 and the filament 18, that providesacceleration of the positive ions to the substrate 12.

[0032] The filament 16 and the filament 18 reside within the vacuumchamber 14 along with a platform 20, which supports the substrate 12. Adrive assembly 22 is shown coupled between a drive motor 24 and a mainshaft of the platform 20 within the vacuum chamber 14. In the embodimentshown in FIG. 1, the platform 20 is provided as a turntable that rotateswithin the vacuum chamber 14. The drive assembly 22 mechanically linksthe rotational motion of the drive motor 24 with the main shaft of theplatform 20 to impart rotation to the platform 20. The rotation of themain shaft of the platform 20 is enhanced through various supportbearings such as a base plate bearing 28 and a platform bearing 30.

[0033] As is illustrated, the vacuum chamber 14 resides or is sealed ona base plate 32. The vacuum chamber 14 may be provided using virtuallyany material that provides the appropriate mechanical characteristics towithstand an internal vacuum and an external pressure, such asatmospheric pressure. For example, the vacuum chamber 14 may be providedas a metal chamber or as a glass bell. In an alternative embodiment, thebase plate 32 serves as the platform 20 to support the substrate 12. Thebase plate 32 may be thought of as part of the vacuum chamber 14.

[0034] The base plate 32 also provides mechanical support for the system10 while allowing various devices to feed through from its bottomsurface to its top surface within the vacuum chamber 14. For example,the filament 16 and the filament 18 receive power from a filament powercontrol module 34. It should be noted that although two filament powercontrol modules 34 are shown in FIG. 1, preferably, these two modulesare implemented as one module. In order to provide power to the filament16 and the filament 18, electrical leads must feed through the baseplate 32 as illustrated in FIG. 1. Similarly, the drive motor 24 mustalso penetrate or feed through the base plate 32 to provide mechanicalaction to the drive assembly 22 so that the platform 20 may be rotated.The electrical feed through 26, described more fully below, also feedsthrough the base plate 32 and provides an electrical conductive pathbetween the platform 20 and various signal generators, also describedmore fully below. In a preferred embodiment, the electrical feed through26 is provided as a commutator that contacts the bottom surface of theplatform 20, in the embodiment where the platform 20 is implemented as aturntable. The electrical feed through 26 may be implemented as acommutator and may be implemented as a metal brush which can contact thebottom surface of the platform 20 and maintain an electrical contacteven if the platform 20 rotates.

[0035] The filament power control module 34 provides an electric currentto the filament 16 and the filament 18. In one embodiment, the filamentpower control module 34 can provide current to the filament 16 for aparticular duration, and then provide current to the filament 18 duringa second duration. Depending upon how the filaments are configured, thefilament power control module 34 may provide current to both thefilament 16 and the filament 18 at the same time or during separateintervals. This flexibility allows more than one particular depositantmaterial to be plasma plated onto the substrate 12 at different times.The filament power control module 34 preferably provides alternatingcurrent to the filaments, but may provide a current using any knownmethod of generating current. In a preferred embodiment, the filamentpower control module 34 provides current at an amplitude or magnitudethat is sufficient to generate enough heat in the filament 16 toevaporate or vaporize the depositant provided therein.

[0036] In order to ensure even heating of the depositant, which will beprovided at or in the filament 16 or the filament 18, the currentprovided by the filament control module 34 will preferably be providedusing incremental staging so that a more even heat distribution willoccur in the depositant that is being melted within the vacuum chamber14.

[0037] In a preferred embodiment, the platform 20 is implemented as aturntable and rotates using the mechanical linkage as described above. Aspeed control module 36, as shown in FIG. 1, may be provided to controlthe speed of the rotation of the platform 20. Preferably, the rotationof the platform 20 occurs at a rate from five revolutions per minutes to30 revolutions per minute. It is believed that an optimal rotationalrate of the platform 20 for plasma plating is provided at a rotationalrate of 12 revolutions per minute to 15 revolutions per minute. Theadvantages of rotating the platform 20 are that the substrate 12 can bemore evenly plated or coated. This is especially true when multiplesubstrates are provided on the surface of the platform 20. This allowseach one of the multiple substrates to be similarly positioned, onaverage, within the vacuum chamber 14 during the plasma plating process.

[0038] In other embodiments, the platform 20 may be provided atvirtually any desired angle or inclination. For example, the platform 20may be provided as a flat surface, a horizontal surface, a verticalsurface, an inclined surface, a curved surface, a curvilinear surface, ahelical surface, or as part of the vacuum chamber such as a supportstructure provided within the vacuum chamber. As mentioned previously,the platform 20 may be stationary or rotate. In an alternativeembodiment, the platform 20 includes rollers that may be used to rotateone or more substrates.

[0039] The platform 20, in a preferred embodiment, provides or includesan electrically conductive path to provide a path between the electricalfeed through 26 and the substrate 12. In one embodiment, platform 20 isprovided as a metal or electrically conductive material such that anelectrically conductive path is provided at any location on the platform20 between the electrical feed through 26 and the substrate 12. In suchas a case, an insulator 21, will be positioned between the platform 20and the shaft that rotates the platform 20 to provide electricalisolation. In another embodiment, the platform 20 includes electricallyconductive material at certain locations on its top surface thatelectrically coupled to certain locations on the bottom surface. In thismanner, the substrate 12 can be placed at an appropriate location on thetop side of the platform 20 while the electrical feed through 26 may bepositioned or placed at an appropriate location on the bottom side ofthe platform 20. In this manner, the substrate 12 is electricallycoupled to the electrical feed through 26.

[0040] The electrical feed through 26 provides a dc signal and a radiofrequency signal to the platform 20 and the substrate 12. The desiredoperational parameters associated with each of these signals aredescribed more fully below. Preferably, the dc signal is generated by adc power supply 66 at a negative voltage and the radio frequency signalis generated by an rf transmitter 64 at a desired power level. The twosignals are then preferably mixed at a dc/rf mixer 68 and provided tothe electrical feed through 26 through an rf balancing network 70, whichprovides signal balancing by minimizing the standing wave reflectedpower. The rf balancing network 70 is preferably controlled through amanual control.

[0041] In an alternative embodiment, the platform 20 is eliminated,including all of the supporting hardware, structures, and equipment,such as, for example, the drive motor 24, and the drive assembly 22. Insuch a case the substrate 12 is electrically coupled to the electricalfeed through 26.

[0042] The remaining equipment and components of the system 10 of FIG. 1are used to create, maintain, and control the desired vacuum conditionwithin the vacuum chamber 14. This is achieved through the use of avacuum system. The vacuum system includes a roughing pump 46 and aroughing valve 48 that is used to initially pull down the pressure inthe vacuum chamber 14. The vacuum system also includes a foreline pump40, a foreline valve 44, a diffusion pump 42, and a main valve 50. Theforeline valve 44 is opened so that the foreline pump 40 can began tofunction. After the diffusion pump 42 is warmed or heated to anappropriate level, the main valve 50 is opened, after the roughing pump46 has been shut in by closing the roughing valve 48. This allows thediffusion pump 42 to further reduce the pressure in the vacuum chamber14 below a desired level.

[0043] A gas 60, such as argon, may then be introduced into the vacuumchamber 14 at a desired rate to raise the pressure in the vacuum chamber14 to a desired pressure or to within a range of pressures. A gascontrol valve controls the rate of the flow of the gas 60 into thevacuum chamber 14 through the base plate 32.

[0044] Once all of the operating parameters and conditions areestablished, as will be described more fully below in connection withFIGS. 5 and 6 according to the teachings of the present invention,plasma plating occurs in system 10. The substrate 12 may be plasmaplated with a deposited layer, which may include one or more layers suchas a base layer, a transitional layer, and a working layer, through theformation of a plasma within the vacuum chamber 14. The plasma willpreferably include positively charged depositant ions from theevaporated or vaporized depositant along with positively charged ionsfrom the gas 60 that has been introduced within the vacuum chamber 14.It is believed, that the presence of the gas ions, such as argon ions,within the plasma and ultimately as part of the depositant layer, willnot significantly or substantially degrade the properties of thedepositant layer. The introduction of the gas into the vacuum chamber 14is also useful in controlling the desired pressure within the vacuumchamber 14 so that a plasma may be generated according to the teachingsof the present invention. In an alternative embodiment, the plasmaplating process is achieved in a gasless environment such that thepressure within the vacuum chamber 14 is created and sufficientlymaintained through a vacuum system.

[0045] The generation of the plasma within the vacuum chamber 14 isbelieved to be the result of various contributing factors such asthermionic effect from the heating of the depositant within thefilaments, such as the filament 16 and the filament 18, and theapplication of the dc signal and the radio frequency signal at desiredvoltage and power levels, respectively.

[0046] The vacuum system of the system 10 may include any of a varietyof vacuum systems such as a diffusion pump, a foreline pump, a roughingpump, a cryro pump, a turbo pump, and any other pump operable or capableof achieving pressures within the vacuum chamber 14 according to theteachings of the present invention.

[0047] As described above, the vacuum system includes the roughing pump46 and the diffusion pump 42, which is used with the foreline pump 40.The roughing pump 46 couples to the vacuum chamber 14 through theroughing valve 48. When the roughing valve 48 is open, the roughing pump46 may be used to initially reduce the pressure within the vacuumchamber 14. Once a desired lower pressure is achieved within the vacuumchamber 14, the roughing valve 48 is closed. The roughing pump 46couples to the vacuum chamber 14 through a hole or opening through thebase plate 32. The roughing pump 46 will preferably be provided as amechanical pump. In a preferred embodiment of the vacuum system of thesystem 10 as shown in FIG. 1, the vacuum system in this embodiment alsoincludes a foreline pump 40 coupled to a diffusion pump 42 through aforeline valve 44. The foreline pump 40 may be implemented as amechanical pump that is used in combination with the diffusion pump 42to reduce the pressure within the vacuum chamber 14 to a level evenlower than that which was produced through the use of the roughing pump46.

[0048] After the roughing pump 46 has reduced the pressure within thevacuum chamber 14, the diffusion pump 42, which uses heaters and mayrequire the use of cooling water or some other substance to cool thediffusion pump 42, couples with the vacuum chamber 14 through a mainvalve 50 and through various holes or openings through the base plate 32as indicated in FIG. 1 by the dashed lines above the main valve 50 andbelow the platform 20. Once the diffusion pump 42 has been heated up andmade ready for operation, the main valve 50 may be opened so that thepressure within the vacuum chamber 14 may be further reduced through theaction of the diffusion pump 42 in combination with the foreline pump44. For example, the pressure within the vacuum chamber 14 may bebrought below 4 milliTorr. During a backsputtering process, the pressurein the vacuum chamber 14 may be dropped to a level at or below 100milliTorr on down to 20 milliTorr. Preferably, the pressure within thevacuum chamber 14 during a backsputtering process will be at a level ator below 50 milliTorr on down to 30 milliTorr. During normal operationof the system 10 during a plasma plating process, the pressure withinthe vacuum chamber 14 may be reduced by the vacuum system to a level ator below 4 milliTorr on down to a value of 0.1 milliTorr. Preferably,the vacuum system will be used during a plasma plating process to reducethe pressure within the vacuum chamber 14 to a level at or below 1.5milliTorr on down to 0.5 milliTorr.

[0049]FIG. 2 is a top view of a vacuum chamber of a system for plasmaplating that illustrates one embodiment of a platform implemented as aturntable 20. The turntable 20 is shown with substrates 12 a, 12 b, 12c, and 12 d positioned, symmetrically on the surface of the turntable20. The turntable 20 may rotate either clockwise or counterclockwise.The substrates 12 a-12 d may be virtually any available material and areshown in FIG. 2 as round, cylindrical components such that the top viewof each of the substrates presents a circular form.

[0050] The filament power control module 34 is electrically coupled to afirst set of filaments 94 and 96 and a second set of filaments 90 and92. Although the electrical connections are not fully illustrated inFIG. 2, it should be understood that the filament power control module34 may supply current to the first set of filaments 94 and 96 or to thesecond set of filaments 90 and 92. In this manner, the deposition layermay be provided with two sublayers such as a base layer and a workinglayer. The base layer will preferably be applied first throughdepositants provided in the first set of filaments 94 and 96 while theworking layer will be deposited on the base layer of the substrates 12a-12 d using the depositants provided at the second set of filaments 90and 92.

[0051] The arrangement of the substrates in FIG. 2 may be described asan array of substrates that include inwardly facing surfaces, which arecloser to the center of the turntable 20, and outwardly facing surfaces,which are closer to the outer edge of the turntable 20. For example, theinwardly facing surfaces of the array of substrates 12 a-d will bepresented to the filament 92 and the filament 96, at different times ofcourse, as they are rotated near the filaments. Similarly, the outwardlyfacing surfaces of the substrates 12 a-d will be presented to thefilaments 90 and 94 as they rotate near these filaments.

[0052] As mentioned previously, the filament power control module 34 mayprovide a current in virtually any form, such as a direct current or analternating current, but preferably provides current as an alternatingcurrent.

[0053] In operation, turntable 20 rotates, for example, in a clockwisedirection such that after substrate 12 b passes near or through thefilaments, the next substrate that will pass near or through thefilaments is substrate 12 c, and so on. In one example, the first set offilaments 94 and 96 are loaded with a depositant, such as nickel (ortitanium), and the second set of filaments are loaded with a depositantsuch as the metal alloy silver\palladium. This example illustrates a twoshot application or a two layer deposition layer.

[0054] After all of the operating parameters have been establishedwithin the vacuum chamber, as described throughout herein, the filamentpower control module 34 may energize or provide alternating current tothe first set of filaments 94 and 96 so that the nickel will evaporateor vaporize to form a plasma with the gas, such as argon gas, within thevacuum chamber. The positively charged nickel ions and the positivelycharged argon ions in the plasma will be attracted to the substrates 12a-d, which are at a negative potential. Generally, the closer thesubstrate is to the first set of filaments 90 and 92 as it rotates, themore material will be deposited. Because the turntable is rotating, auniform or more even layer will be applied to the various substrates.

[0055] After the first plasma has been plated onto the array ofsubstrates 12 a-d to form a base layer of the depositant layer on thesubstrates, the filament power control module 34 is energized so that asufficient amount of current is provided to the second set of filaments90 and 92. Similarly, a plasma is formed between the argon ions and thesilver\palladium ions and the working layer is then formed to thesubstrates that are being rotated.

[0056] During the first shot when the base layer is being applied, theoutwardly facing surfaces of substrates 12 a-d are primarily coatedthrough the nickel depositant located in the filament 94. Similarly, theinwardly facing surfaces of the substrates are coated by the nickeldepositant located in the filament 96. The same relation holds true forthe second shot where the silver\palladium is plasma plated onto thesubstrates to form the deposit layer.

[0057]FIG. 3 is a side view that illustrates the formation anddispersion of a plasma around a filament 100 to plasma plate a substrate12 according to an embodiment of the present invention. The filament 100is implemented as a wire basket, such as tungsten wire basket, and isshown with a depositant 102 located within, and mechanically supportedby, the filament 100. As the filament power control module 34 providessufficient current to the filament 100, the depositant 102 melts orvaporizes and a plasma 104 is formed. Of course, all of the operatingparameters of the present invention must be present in order to achievethe plasma state so that plasma plating may take place.

[0058] The substrate 12, which is provided at a negative potential,attracts the positive ions of the plasma 104 to form a deposition layer.As is illustrated, the dispersion pattern of the plasma 104 results inmost of the positive ions of the plasma 104 being attracted to the sideadjacent or nearest to the filament 100 and the depositant 102. Somewrap around will occur such as that illustrated by the plasma 104contacting the top surface of the substrate 12. Similarly, some of thepositive ions of the plasma 104 may be attracted to the platform orturntable. As is illustrated, the present invention provides anefficient solution for the creation of a deposition layer by ensuringthat most of the ions from the depositant are used in the formation ofthe deposition layer.

[0059]FIG. 4 is a sectional view that illustrates a deposition layer ofthe substrate 12 that includes a base layer 110, a transition layer 112,and a working layer 114. It should be noted at the outset that thethickness of the various layers that form the deposition layer aregrossly out of proportion with the size of the substrate 12; however,the relative thicknesses of the various sublayers or layers of thedeposition layer are proportionate to one another, according to oneembodiment of the present invention.

[0060] Generally, the thickness of the entire deposition layer on thesubstrate, according to the teachings of the present invention, arebelieved to generally range between 500 and 20,000 Angstroms. In apreferred embodiment, the entire thickness of the deposition layer isbelieved to range between 3,000 and 10,000 Angstroms. The presentinvention provides excellent repeatability and controllability ofdeposition layer thicknesses, including all of the sublayers such as thebase layer 110, the transition layer 112, and the working layer 114. Itis believed that the present invention can provide a controllable layerthickness at an acuracy of around 500 Angstroms. It should also bementioned that the present invention may be used to form a depositionlayer with one or any multiple of sublayers.

[0061] The thickness of the deposition layer is normally determinedbased on the nature of intended use of the plasma plated substrate. Thismay include such variables as the temperature, pressure, and humidity ofthe operating environment, among many other variables and factors. Theselection of the desired metal or depositant type for each layer is alsohighly dependant upon the nature of the intended use of the plasmaplated substrate.

[0062] For example, the present invention prevents or substantiallyreduces galling or mating or interlocking components. Galling includesthe seizure of mated components that often occur when two surfaces, suchas threaded surfaces, are loaded together. Galling can cause componentsto fracture and break, which often results in severe damage. Plasmaplating may be used to prevent or reduce galling by plating one or morecontacting surfaces.

[0063] Various depositants may be used to achieve this beneficialeffect. It is believed, however, that galling is preferably reducedthrough a plasma plating process that deposits a base layer of nickel ortitanium and a working layer of a silver/palladium metal alloy on one ormore contacting surfaces. For high temperature applications, such asover 650 degrees Fahrenheit, it is believed that the galling ispreferably reduced through a plasma plating process that deposits anickel or titanium base layer and a working layer of gold.

[0064] It has been found through experimentation that chromium does notwork well to reduce galling, this includes when the chromium isdeposited as either the base layer, the transition layer, or the workinglayer. It is believed that chromium may be a depositant that is moredifficult to control during the plasma plating process.

[0065] Plasma plating may also be used to plate valve parts, such asvalve stems in nonnuclear applications, and are preferably plasma platedusing a titanium base layer, a gold transition layer, and an indiumworking layer. In nuclear applications, such as nuclear power plantapplications, indium is not a preferred plasma plating depositantbecause it is considered to be too much of a radioactive isotopeabsorber. Instead, valve stems in nuclear applications are preferablyplasma plated using a nickel base layer and a silver/palladium metalalloy working layer.

[0066] As is illustrated in FIG. 4, the working layer 14 is normallyprovided at a substantially larger thickness than the correspondingtransition layer 112 and the base layer 110. It should also be notedthat the coating of the top of the substrate 12 is shown to be thin ator near the center or middle of the substrate 12. This effect is due tohow the filaments are positioned during the plasma plating process. Forexample, if the filaments are positioned similarly to that illustratedin FIGS. 2-3, the middle or center portion of the substrate 12 willgenerally have a thinner overall profile than the side of the depositionlayer.

[0067] Although various ranges of thicknesses have been discussedherein, it should be understood that the present invention is notlimited to any maximum deposition layer thickness. The thickness of thedeposition layer, especially the thickness of the working layer 114, canbe provided at virtually any desired thickness, normally depending uponthe operating environment in which the plasma plated substrate 12 willbe introduced. The base layer 110 and the transition layer 112 and anyother layers below the working layer 114 will preferably be provided ata substantially smaller thickness than the corresponding thickness ofthe working layer 114. For example, the base layer 110 and thetransition layer 112 may be provided at a thickness ranging from 500 to750 Angstroms while the working layer 114 may be provided at virtuallyany thickness such as for example 18,000 Angstroms.

[0068]FIG. 5 is a flow chart of a method 500 for plasma platingaccording to an embodiment of the present invention. The method 500begins at block 502 and proceeds to block 504. At block 504, thematerial or substrate that will be plasma plated is prepared for theprocess. This may include cleaning the substrate to remove any foreignmaterials, contaminants, and oils. Any of a variety of known cleaningprocesses may be used such as those defined by the Steel StructuresPainting Council (SSPC). For example, the SSPC-5 standard may beemployed to ensure that a substrate is cleaned to a white metalcondition. Similarly, the SSPC-10 standard may be employed. Preferably,the substrate will undergo an abrasive blasting, such as for example,bead blasting to further ensure that any foreign materials orcontaminants are removed. It should be noted that an oxidation layer maybe present on the surface of the substrate. The present invention allowsfor a deposition layer to be plasma plated onto the substrate surface,even in the presence of an oxidation layer, with excellent adhesion andmechanical properties.

[0069] The method 500 proceeds next to block 506 where the plasmaplating system prerequisites are established. Depending upon theimplementation of the system for plasma plating, this may involve any ofa variety of items. In the situation where a diffusion pump is used aspart of the vacuum system, items such as the availability of coolingwater must be established. Similarly, the adequate availability of lubeoil and air to operate the various equipment, valves, and machineryassociated with the system for plasma plating must be established. Anadequate supply of gas, such as argon gas, should also be verified andchecked at this point before proceeding to block 510.

[0070] At block 510, assuming that a diffusion pump is used as part ofthe vacuum system, the diffusion pump is prepared for operation. Thismay include opening a foreline valve and the starting of the forelinevacuum pump which is used in combination with the diffusion pump. Once aforeline vacuum has been drawn, the heaters of the diffusion pump may beenergized. This places the diffusion pump in service.

[0071] The method 500 proceeds next to block 512 where the vacuumchamber is set up. This includes any number of processes such aspositioning the substrate within the vacuum chamber. This is normallyachieved by positioning or placing the substrate at a specified locationon a platform or turntable located within the vacuum chamber. Beforeaccessing the internal volume of the vacuum chamber, the vacuum chamberseal must be broken and the bell jar or outer member is preferablylifted away from its base plate. Once the substrate is positioned on theplatform, the filaments may be positioned relative to the placement ofthe substrate.

[0072] The positioning of the filaments may involve any number oftechniques and includes such variables as the amount and type ofdepositant to be provided at the filament, and the distance, not onlyrelative to the substrate, but relative to other filaments. Generally,the filament will be located a distance ranging from 0.1 inches to 6inches from the substrate, as measured from the center line of thefilament, or from the depositant, to the closest point of the substrate.Preferably, however, the distance between the filament or the depositantand the substrate will range anywhere from 2.75 inches to 3.25 incheswhen the depositant will serve as the base layer or transition layer ofthe deposition layer. Similarly, when the depositant will serve as theworking layer of the deposition layer that will be deposited on thesubstrate, the distance between the filament or the depositant and thesubstrate is preferably provided at a distance between 2 inches and 2.5inches.

[0073] In the situation where multiple depositants or multiple shotswill be performed in the plasma plating process, it is necessary toconsider the placement of the filaments that will hold the firstdepositant relative to those that will hold the second depositant aswell as each of the filament's position relative to each other and thesubstrate. Generally the distance of a second filament from a firstfilament, which will include a depositant that will serve as a baselayer, transition layer, or a working layer of a deposition layer,should be anywhere between 0.1 inches and 6 inches.

[0074] The spacing between filaments that include depositants that willserve as a base layer, is generally provided between 0.1 inches and 6inches. Preferably, this distance shall be between 3 inches and 4inches. The foregoing filament spacing information also applies when thedepositant provided in the filaments will serve as the transition layerin the deposition layer. Similarly, the spacing between filaments, whichinclude a depositant that will serve as the working layer of thedeposition layer, should generally be between 0.1 inches and 6 inches,but, preferably, will be between 2.5 inches and 3 inches.

[0075] The chamber setup of block 512 may also need to take into accountthe arrangement of an array of substrates on the platform that are beingplasma plated. For example, a filament that is positioned in the vacuumchamber so that it will provide a dispersion pattern to providedepositant coverage to inwardly facing surfaces of an array ofsubstrates, it may require anywhere from 20 to 80 percent less mass orweight of depositant when compared with a filament positioned in thevacuum chamber to provide coverage for the array of outwardly facingsurfaces. The reference to inwardly and outwardly are relative to theplatform or turntable with inwardly referring to those surfaces closerto the center of the platform or turntable. This is because theefficiency of the plasma plating process is greater for the inwardlyfacing surfaces of an array of substrates than at the outwardly facingsurfaces of the array of substrates because of the forces attractingthe, generally, positive ions of the plasma. This also ensures that thethickness of the deposition layer on the inwardly facing surfaces andthe outwardly facing surfaces are more uniform. In such a case, theweight or mass of the depositant will, preferably, need to vary betweensuch filament positions. Generally, the variance in mass or weightbetween the two locations may be anywhere from 20 to 80 percentdifferent. Preferably, the depositants in the filaments covering theinwardly facing surfaces will use 40 to 50 percent less mass or weightthan the depositants of the filaments covering the outwardly facingsurfaces. The amount of the depositant placed in the filamentscorresponds to the desired thickness of the deposition layer, and anysublayers thereof. This was discussed more fully and is illustrated morefully in connection with FIG. 3.

[0076] The type of filament affects the dispersion pattern achievedthrough the melting or evaporation of its depositant during the creationof the plasma. Any of a variety of filament types, shapes, andconfigurations may be used in the present invention. For example, thefilament may be provided as a tungsten basket, a boat, a coil, acrucible, a ray gun, an electron beam gun, a heat gun, or as any otherstructure, such as a support structure provided within the vacuumchamber. The filaments are generally heated through the application ofan electric current through the filament. However, any method or meansof heating the depositant within the filament may be used in the presentinvention.

[0077] The setup of the vacuum chamber also includes placing thedepositants in the one or more filaments. The present inventioncontemplates the use of virtually any material that is capable of beingevaporated under the conditions and parameters of the present inventionso that a plasma will form. For example, the depositant may includevirtually any metal, such as a metal alloy, gold, titanium, chromium,nickel, silver, tin, indium, lead, copper, palladium, silver/palladiumand any of a variety of others. Similarly, the depositant may includeany other materials such as carbon, nonmetals, ceramics, metal carbides,metal nitrates, and any of a variety of other materials. The depositantswill generally be provided in a pellet, granule, particle, powder, wire,ribbon, or strip form. Once the filaments have been properly positionedand loaded, the vacuum chamber may be closed and sealed. This mayinclude sealing the bell portion of the vacuum chamber with its baseplate.

[0078] The method 500 proceeds next to block 514 where preparations aremade to begin establishing a vacuum condition within the vacuum chamber.In one embodiment, such as the system 10 shown in FIG. 1, a roughingpump is started to begin evacuating the vacuum chamber and to bring thepressure down within the vacuum chamber to a sufficient level so thatadditional pumps may take over to further reduce the pressure within thevacuum chamber. In one embodiment, the roughing vacuum pump is amechanical pump that may be started, and a roughing valve may then beopened to provide access to the vacuum chamber. Once the roughing vacuumpump has achieved its desired function and has reduced the pressure inthe vacuum chamber to its desired or designed level, the roughing valveis shut. At this point, the method 500 transitions to block 516.

[0079] At block 516, the pressure within the vacuum chamber is furtherreduced using another vacuum pump. For example, in one embodiment, adiffusion pump/foreline pump is utilized to further reduce the pressurewithin the vacuum chamber. In the embodiment of the present invention asillustrated in FIG. 1, this is achieved by opening the main valve andallowing the diffusion pump, supported by the mechanical foreline pump,to further pull or reduce the pressure in the vacuum chamber.

[0080] Generally, the pressure in the vacuum chamber is reduced to alevel that is at or below 4 milliTorr. Preferably, the pressure in thevacuum chamber is reduced to a level that is at or below 1.5 milliTorr.In the event that backsputtering, which is described below in connectionwith block 518 of the method 500, is to be performed, the pressure inthe vacuum chamber is reduced to a level below 100 milliTorr andgenerally in a range between 20 milliTorr and 100 milliTorr. In apreferred embodiment when backsputtering is to be performed, thepressure is reduced in the vacuum chamber at a level below 50 milliTorr,and generally at a level between 20 milliTorr and 50 milliTorr.

[0081] Preceding next to block 518, a backsputtering process may beperformed to further clean and prepare the substrate. It should beunderstood, however, that such a process is not mandatory. Thebacksputtering process is described in more detail below in connectionwith FIG. 6. The backsputtering process may include the rotation of theplatform or turntable within the vacuum chamber. In such a case, theturntable will generally be rotated at a rate at or between 5revolutions per minute and 30 revolutions per minute. Preferably, theturntable will be rotated at a rate between 12 revolutions per minuteand 15 revolutions per minute. The operation of the turntable, whichalso will preferably be used as the deposition layer is being formed onthe substrate according to the teachings of the present invention.

[0082] Method 500 proceeds next to block 520 where an operating vacuumis established. Although a vacuum condition has already been establishedwithin the vacuum chamber, as previously discussed in connection withblock 514 and 516, an operating vacuum can now be established throughthe introduction of a gas into the vacuum chamber at a flow rate thatwill raise the pressure in the vacuum chamber to a level generally at orbetween 0.1 milliTorr and 4 milliTorr. Preferably, the introduction ofthe gas is used to raise the pressure in the vacuum chamber to a levelthat is at or between 0.5 milliTorr and 1.5 milliTorr. This will ensurethat there are no depositant ion collisions within the plasma, whichwill increase the depositant efficiency and provide a clean, highlyadhered deposition layer to the substrate. The gas that is introducedinto the vacuum chamber may be any of a variety of gases but willpreferably be provided as an inert gas, a noble gas, a reactive gas or agas such as argon, xenon, radon, helium, neon, krypton, oxygen,nitrogen, and a variety of other gases. It is desirable that the gas isa noncombustible gas. It should be understood that the present inventiondoes not require the introduction of a gas but may be performed in theabsence of a gas.

[0083] At block 522, various operating parameters and values of thesystem are established. This will generally include the rotation of aturntable, if desired, the application of a dc signal, and theapplication of a radio frequency signal. Assuming that the platformincludes a turntable or some other rotating device, the turntablerotation will preferably be established at this point. This assumes, ofcourse, that the rotation of the turntable was not previously startedand the discretionary backsputtering block 518. Once the rotation of theturntable has been established, the dc signal and the rf signal may beapplied to the substrate. The application of the dc signal to thesubstrate will generally be provided at a voltage amplitude that is ator between one volt and 5,000 volts. Note that the polarity of thevoltage will preferably be negative; however, this is not alwaysrequired. In a preferred embodiment, the application of the dc signal tothe substrate will be provided at a voltage level at or between negative500 volts and negative 750 volts.

[0084] The application of the radio frequency signal to the substratewill generally be provided at a power level that is at or between 1 wattand 50 watts. Preferably, the power level of the radio frequency signalwill be provided at 10 watts or between a range defined by 5 watts and15 watts. The frequency of the radio frequency signal will generally beprovided at an industrial specified frequency value in either thekilohertz range or the megahertz range. Preferably, the frequency signalwill be provided at a frequency of 13.56 kilohertz. Although the termradio frequency has been used throughout to describe the generation andapplication of the radio frequency signal to the substrate, it should beunderstood that the term radio frequency should not be limited to itscommonly understood definition of signals having frequencies roughlybetween 10 kilohertz and 100,000 megahertz. The term radio frequencyshall also include any signal with a frequency component that isoperable or capable of assisting with the creation or excitation of aplasma in a vacuum chamber.

[0085] Block 522 will also preferably include the mixing of the dcsignal and the radio frequency signal, using mixer circuitry, togenerate a mixed signal. This allows only one signal to be applied tothe substrate. This is generally achieved using the electrical feedthrough that extends through the base plate of the vacuum chamber andcontacts an electrically conductive portion of the platform, which inturn electrically couples to the substrate or substrates. Block 522 mayalso include the balancing of the mixed signal through the use of aradio frequency balancing network. Preferably, the mixed signal isbalanced by minimizing the standing wave reflected power. This ispreferably controlled through a manual control.

[0086] As the output or load characteristics of the antenna or outputchanges, as seen from the mixer circuitry, problems can arise whenelectrical signals or waves are reflected from the output load back tothe mixer or source. These problems may include damage to the radiofrequency transmitter and a reduction in the transfer of power to thesubstrate and vacuum chamber to ensure the formation of a sufficientplasma to achieve a successful plasma plating process.

[0087] This problem can be reduced or solved by including the radiofrequency balancing network that can adjust its impedance, including inone embodiment its resistance, inductance, and capacitance, to match orreduce the presence of reflected waves. The impedance and electricalcharacteristics of the output load or antenna are affected by suchthings as the presence and/or absence of a plasma and the shape andproperties of the substrate or substrates on the platform. Because ofsuch changes during the plasma plating process, the radio frequencybalancing network may need to be adjusted during the process to minimizethe standing wave reflected power or, stated differently, to prevent orreduce the standing wave ratio return to the radio frequencytransmitter. Preferably, these adjustments are performed manually by anoperator during the plasma plating process. In other embodiments, theradio frequency balancing network is automatically adjusted. Care mustbe taken, however, to ensure that the automatic adjustment does not overcompensate or poorly track the changes in the output load.

[0088] The method 500 proceeds next to block 524 where the depositant ordepositants are melted or evaporated so that a plasma will be generated.The generation of the plasma at the conditions provided by the presentinvention will result in a deposition layer being formed on the surfaceof the substrate through plasma plating. It is believed that thedeposition layer is formed at a medium energy level on the average ofbetween 10 eV and 90 eV.

[0089] The depositants are generally evaporated or vaporized byproviding a current through the filament around the depositant. In apreferred embodiment, the depositants are slowly or incrementally heatedto achieve a more even heat distribution in the depositant. This alsoimproves the formation of the plasma. The current may be provided as analternating current or as any other current that is sufficient togenerate heat in the filament that will melt the depositant. In otherembodiments, the depositant may be heated through the introduction of anagent that is in chemical contact with the depositant. In still otherembodiments, the depositant may be heated through the use ofelectromagnetic or microwave energy.

[0090] The conditions in the vacuum chamber will be correct for theformation of a plasma. The plasma will generally include gas ions, suchas argon ions, and depositant ions, such as gold, nickel, or palladiumions. The gas ions and the depositant ions will generally be provided aspositive ions due to the absence of one or more electrons. The creationof the plasma is believed to be assisted through the introduction of theradio frequency signal and because of thermionic phenomena due to theheating of the depositants. It is contemplated that in some situations,a plasma may be generated that includes negatively charged ions.

[0091] The negative potential established at the substrate due to the dcsignal will attract the positive ions of the plasma. Once again, thiswill primarily include depositant ions and may include gas ions, such asargon gas ions from the gas that was introduced earlier in method 500.The inclusion of the gas ions, such as argon ions, are not believed todegrade the material or mechanical characteristics of the depositionlayer.

[0092] It should be noted that some prior literature has suggested thatthe introduction of a magnet at or near the substrate is desirable toinfluence the path of the ions of the plasma as they are attracted tothe substrate to form the deposition layer. Experimental evidence nowsuggests that the introduction of such a magnet is actually undesirableand produced unwanted effects. The presence of the magnet may lead touneven deposition thicknesses, and prevent or significantly impede thecontrollability, repeatability, and reliability of the process.

[0093] Whenever the deposition layer is designed to include multiplesublayers, multiple shots must be performed at block 524. This meansthat once the base layer depositants have been melted through theheating of their filaments, the transition layer depositants (or thedepositant of the next layer to be applied) are heated and melted by theintroduction of heat at their filaments. In this manner, any number ofsublayers may be added to the deposition layer. Before successivedepositant sublayers are formed, the preceding layer shall have beenfully or almost fully formed. The method 500 thus provides thesignificant advantage of allowing a deposition layer to be createdthrough multiple sublayers without having to break vacuum andreestablish vacuum in the vacuum chamber. This can significantly cutoverall plasma plating time and costs.

[0094] The method 500 proceeds next to block 526 where the process orsystem is shut down. In the embodiment of the system shown in FIG. 1,the main valve is closed and a vent valve to the vacuum chamber isopened to equalize pressure inside the vacuum chamber. The vacuumchamber may then be opened and the substrate items may be immediatelyremoved. This is because the method 500 does not generate excessive heatin the substrates during the plasma plating process. This providessignificant advantages because the material or mechanical structure ofthe substrate and deposition layer are not adversely affected byexcessive temperature. The plasma plated substrates may then be used asneeded. Because the temperature of the substrates are generally at atemperature at or below 125 Fahrenheit, the substrates can generally beimmediately handled without any thermal protection.

[0095] The method 500 provides the additional benefit of not generatingany waste byproducts and is environmentally safe. Further, the method500 is an efficient process that efficiently uses the depositants suchthat expensive or precious metals, such as gold and silver, areefficiently utilized and are not wasted. Further, due to the fact thatthe present invention does not use high energy deposition techniques, noadverse metallurgical or mechanical effects are done to the substrate.This is believed to be due to the fact that the deposition layer of thepresent invention is not deeply embedded within the substrate, butexcellent adherence, mechanical, and material properties are stillexhibited by the deposition layer. After the substrates have beenremoved at block 528, the method 500 ends at block 530.

[0096]FIG. 6 is a flow chart of a method 600 for backsputtering usingthe system and method of the present invention, according to anembodiment of the present invention. As mentioned previously,backsputtering may be used to further clean the substrate before adeposition layer is formed on the substrate through plasma plating.Backsputtering generally removes contaminants and foreign materials.This results in a cleaner substrate which results in a stronger and moreuniform deposition layer. The method 600 begins at block 602 andproceeds to block 604 where a gas is introduced into the vacuum chamberat a rate that maintains or produces a desired pressure within thevacuum chamber. This is similar to what was previously described inblock 520 in connection with FIG. 5. Generally, the pressure in thevacuum chamber should be at a level at or below 100 milliTorr, such asat a range between 20 milliTorr and 100 milliTorr. Preferably, thepressure is provided at a level at or between 30 milliTorr and 50milliTorr.

[0097] The method 600 proceeds next to block 606 where rotation of theplatform or turntable is established, if applicable. As mentionedpreviously, the rotation of the turntable may be provided at a ratebetween 5 revolutions per minute and 30 revolutions per minute but ispreferably provided at a rate between 12 revolutions per minute and 15revolutions per minute.

[0098] Proceeding next to block 608, a dc signal is established and isapplied to the substrate. The dc signal will generally be provided at anamplitude at or between one volt and 4,000 volts. Preferably, the dcsignal will be provided at a voltage between negative 100 volts andnegative 250 volts.

[0099] Block 608 also involves the generation of a radio frequencysignal that will be applied to the substrate. The radio frequency signalwill generally be provided at a power level at or between 1 watt and 50watts. Preferably, the radio frequency signal will be provided at apower level of 10 watts or at or between 5 and 15 watts. The dc signaland the radio frequency signal are preferably mixed, balanced, andapplied to the substrate as a mixed signal. As a consequence, a plasmawill form from the gas that was introduced at block 604. This gas willgenerally be an inert gas or noble gas such as argon. The formation ofthe plasma includes positive ions from the gas. These positive ions ofthe plasma will be attracted and accelerated to the substrate, whichwill preferably be provided at a negative potential. This results incontaminants being scrubbed or removed from the substrate. Once thecontaminants or foreign matter are removed from the substrate, they aresucked out of the vacuum chamber through the operation of the vacuumpump, such as the diffusion pump.

[0100] Proceeding next to block 610, the backsputtering processcontinues for a period of time that is generally between 30 seconds andone minute. Depending on the condition and cleanliness of the substrate,the backsputtering process may continue for more or less time.Generally, the backsputtering process is allowed to continue until thecapacitance discharge, created by the backsputtering process issubstantially complete or is significantly reduced. This may be visuallymonitored through the observation of sparks or light bursts thatcoincide with the capacitive discharge from the contaminants from thesubstrate. This may be referred to as microarcing.

[0101] During the backsputtering process, the dc signal must becontrolled. This is normally achieved through manual adjustments of a dcpower supply. Preferably, the voltage of the dc signal is provided at alevel that allows the voltage to be maximized without overloading the dcpower supply. As the backsputtering process continues, the current inthe dc power supply will vary because of changes in the plasma thatoccur during the backsputtering process. This makes it necessary toadjust the voltage level of the dc signal during the backsputteringprocess.

[0102] The method 600 proceeds next to block 612 where the dc signal andthe radio frequency signal are removed and the gas is shut off. Themethod 600 proceeds next to block 614 where the method ends.

[0103]FIG. 7 is a front view of a vacuum chamber 700 for use in aconfigurable vacuum system according to an embodiment of the presentinvention. The vacuum chamber 700 is shown as a cylindrical type vacuumchamber with a vacuum chamber door 702 hingeably mounted to the mainopening of the vacuum chamber 700, and a leg 710 and a leg 708positioned to support the vacuum chamber 700. The hingeable coupling orconnection between the vacuum chamber door 702 to the main opening ofthe vacuum chamber 700 is illustrated by hinge 712. The vacuum chamber700 may be made of any of a variety of materials such as, for example,metal, steel, or a composite. A railing 704 and a railing 706 are shownwithin the internal volume of the vacuum chamber 700 and are illustratedmounted or coupled to the internal walls of the vacuum chamber 700.These railings are used to support a vacuum table assembly that may beslid in or rolled into the internal volume of the vacuum chamber 700using or while supported by the railing 704 on one side and the railing706 on the other.

[0104] Various types of connectors may also be provided within theinterior of vacuum chamber 700 to couple with various connectors of thevacuum table assembly. These connectors allow electric power (orcurrent), electrical signals, and mechanical power, for example, to beprovided to the vacuum table assembly during the plating process andwhen vacuum conditions exist within the vacuum chamber 700. Theseconnections may be automatically made when the vacuum table assembly ispositioned within the internal volume of the vacuum chamber 700. Thismay significantly increase overall productivity of the plating processby allowing various plating or coating batches to be efficiently andquickly performed.

[0105] The connections may, for example, and as was discussed previouslyin relation to FIG. 1, during a plasma plating process provide a currentto the various filaments of the vacuum table assembly that containdepositants so that the depositants can be heated and evaporated duringplating. This current may be generated and provided by a filament powercontrol module, as shown in FIG. 1. Similarly, if the vacuum tableassembly needs mechanical energy, such as rotational motion at asubstrate, connections may provide such mechanical power from outside towithin the vacuum chamber to provide the needed rotation. If the vacuumtable assembly requires an electrical signal, such as that provided bythe electrical feed through 26 as shown in FIG. 1 and describedpreviously, connections and conductors may provide such a path. Thevacuum chamber 700 provides interfaces or connectors for electricalpower, electrical signals, and mechanical power so that external sourcesof such power and signals can be provided to the internal volume of thevacuum chamber 700 during a deposition process from external sources.

[0106] Examples of such connectors or couplings are shown within thevacuum chamber 700. A filament power connector 714 is shown towards thebottom of the vacuum chamber 700 and includes various conductors thatelectrically couple with various contact pads, such as a filament powercontact pad 716 as illustrated in FIG. 7. Each of the various contactpads of the filament power connector 714 will, preferably, automaticallycouple with a corresponding contact pad of the vacuum table assemblywhen it is inserted into the vacuum chamber 700. The power may then berouted to various filaments, filament power conductors, which,preferably, provide mechanical support to the filaments and may bepositioned in any of a number of arrangements on the vacuum tableassembly. A electrical feed through connector 718 is shown along with amechanical drive connector 720 at the back and within the vacuum chamber700.

[0107] When the vacuum table assembly slides or fits within the vacuumchamber 700, it will contain corresponding connectors that willpreferably, automatically couple to these connectors with correspondingmating connectors. The mechanical drive connector 720 providesmechanical rotational energy to a mechanical drive or drive shaft of thevacuum table assembly. The electrical feed through connector 718provides an electrical coupling to an electrical feed through, similarto the electrical feed through 26 that was shown and illustrated inconnection with FIG. 1. Ultimately, this provides a conductive path sothat an electrical signal, such as a dc/rf signal, can be provided tothe vacuum table assembly during plating and while vacuum conditionsexist in the vacuum chamber 700. For example, the electrical signal maybe a dc/rf signal, which is ultimately provided at the substrate, whenthe coating or plating process used is plasma plating.

[0108]FIG. 8 is a bottom view of a support frame 730 that may be used ina vacuum table assembly 732 according to one embodiment of the presentinvention. The support frame 730 may be provided in virtually anyavailable structure and arrangement. For example, the support frame 730may be implemented using unistruts that include both horizontal andvertical members. On a first parallel side 734 one or more wheels may bemounted such as wheel or roller 738. Similarly, a second parallel sidemay include various wheels or rollers as is illustrated in FIG. 8. Thesewheels or rollers will assist in placing, sliding, or rolling the vacuumtable assembly 732 into the vacuum chamber 700. For example, the rollersor wheels of the first parallel side 734 and the second parallel side736 may be provided at the railing 704 and the railing 706,respectively, of the vacuum chamber 700. This greatly assists with theplating process.

[0109]FIG. 9 is a bottom view of the support frame 730 as shown andillustrated in FIG. 8 with the addition of a filament power connector740 coupled or positioned relative to the support frame 730. When thevacuum table assembly 732 is wheeled or slid into the vacuum chamber700, the filament power connector 740 may couple, preferably,automatically to the filament power connector 714 as illustrated in FIG.7. Similarly, all of the various contacts of the two filament powercontrol connectors 740 and 714 will mate or couple. This may be achievedin a preferred embodiment using spring-loaded contact pads such as afilament power contact pad 742 and the filament contact pad 716 as shownin FIG. 7.

[0110]FIG. 10 is a bottom view of the support frame 730 as shown andillustrated in FIG. 8 with the addition of a mechanical drive 750coupled to the support frame 730 and an electrical feed through 760coupled to the support frame or positioned on or near the support frameaccording to an embodiment of the present invention. The filament powerconnector 740, as was illustrated in FIG. 9, is not shown in FIG. 10 inorder to simplify the discussion and understanding of the vacuum tableassembly 732.

[0111] Focusing on the mechanical drive 750, a mechanical driveconnector 752 is shown at one end. This will couple to the correspondingmechanical drive connector 720 of the vacuum chamber 700 when the vacuumtable assembly 732 is positioned within the vacuum chamber 700. Themechanical drive 750 is shown as a shaft that is mounted to across-member 758 and a cross-member 780 of the support frame 730. Themechanical drive 750 is also shown positioned generally within thecenter of the support frame 730 but, in other embodiments, it may beoffset to one side or the other. The mechanical drive 750 receivesrotational mechanical energy at the mechanical drive connector 752 suchthat the mechanical drive 750 shaft rotates. This rotational energy mayrotate a gearbox 754 which translates the rotational energy of themechanical drive 750 into a second rotational energy operable to drivethe rotation of a platform, not shown in FIG. 10. The platform orturntable will preferably be mounted on the other side or the top of thesupport frame 730. The substrate that is to be plated will generally beplaced on the platform. The gearbox 754 may use a drive assembly, suchas a belt drive or direct drive to couple with the bottom of theplatform.

[0112] A gear 756 may also be provided on the mechanical drive 750 suchthat the rotation of the mechanical drive 750 also rotates the gear 756.The gear 756 may be implemented, in another embodiment, as a pulley thatuses a belt to drive a platform that is implemented as a roller. Thiswill be illustrated more fully below. The gear 756, just like thegearbox 754, provides rotational energy to a platform so that asubstrate may be rotated as desired.

[0113] Focusing now on the electrical feed through 760, an electricalfeed through connector 762 is shown at cross-member 758. The electricalfeed through connector 762 will, preferably, automatically couple withthe electrical feed through connector 718 of the vacuum chamber 700. Theelectrical feed through 760 provides an electrical or conductive path sothat an electrical signal, such as a dc/rf signal, may be providedultimately to a substrate to assist with plating, such as when plasmaplating is used. A second end 764 of the electrical feed through 760 mayinclude a commutator, such as a brush or spring-loaded roller so that anelectrical path is provided to the substrate that is being plated. Thecommutator, such as when the spring-loaded roller is used, may directlycontact the substrate as it is being rotated, or the commutator mayelectrically contact a platform, such as a turntable or conductive plateso that an electrical path is provided to the substrate during plating,thus allowing the electrical signal to be provided at the substrate asdesired.

[0114]FIG. 11 is a top view of an insulated surface 800 positioned onthe support frame 730, and two support members 802 and 804 of the vacuumtable assembly 732. The support frame 730 is not visible from this view.The insulated surface 800 may be implemented using virtually any knownor available material such as micarta. Preferably, the insulated surface800 provides some level of rigidity and mechanical support so thatfilament rods, bars or conductors may be mounted through the insulatedsurface 800 so that various filaments may be positioned as desired onthe top of the insulated surface 800. The insulated surface 800 is alsoshown with an opening 806 provided through its surface. It should benoted that any of a variety of openings or holes may be provided asdesired and needed through the insulated surface 800. This allows formechanical and electrical feed throughs to be provided from the bottomof the insulated surface 800 to the top of the surface of the insulatedsurface 800. For example, the mechanical drive 750 and the electricalfeed through 760 will ultimately be provided through an opening in theinsulated surface 800.

[0115] The support member 802 and support member 804 are used to providea support structure so that any of a variety of various platforms may bemounted on the top of the vacuum table assembly 732. In one embodiment,the support members 802 and 804 are implemented as metal unistrutmembers that are coupled to the support frame 730 on the bottom side ofthe insulated surface 800. The unistrut provides valuable versatilityand coupling various platforms such as turntables, rollers, andconductive plates, to the vacuum table assembly 732.

[0116] The bottom side of the insulated surface 800 will, preferably,provide any of a variety of conductive paths or wires so that thefilament power contact pads of the filament power connector 714 willcouple through such conductors or paths to a desired location on theinsulated surface 800. Holes or openings will then be made in theinsulated surface 800 so that filament conductors may be providedthrough such holes, while still electrically coupled to the filamentpower connector 714. This allows filaments to be positioned as desiredand virtually anywhere on the top surface of the insulated surface 800.

[0117]FIGS. 12a-b is a top and side view of the vacuum table assembly732 illustrating a filament 820, which is mechanically supported by afirst filament conductor 822 and a second filament conductor 824. Thefirst filament conductor 822 and the second filament conductor 824 alsoprovide an electrical path, as just discussed above, back to the desiredpad of the filament power connector 740.

[0118] A platform 830 is shown mounted using the support members 804 and802 and a belt being driven by the gearbox 754 of the mechanical drive750 through an opening in the insulated surface 800 using a belt 832coupled to the base underneath the table or platform 830. A substratemay be provided on the top surface of the platform 830 for coating. Acommutator, not shown in FIG. 12a, is provided through the insulatedsurface 800 at the second end 764 of the electrical feed through 760such that the commutator touches the bottom portion of the platform 830,which provides an electrical path to the top surface of the platform 830and thus to the substrate to be coated.

[0119]FIG. 12b generally shows a side view of FIG. 12a with the vacuumtable assembly 732 implemented within the internal volume of the vacuumchamber 700. A commutator 840 is shown coupled to the electrical feedthrough 760 and electrically coupled to the bottom surface of theplatform 830. As is also illustrated, the various mechanical andelectrical connections are shown to correlate as the vacuum tableassembly 732 is provided within the internal volume of the vacuumchamber 700.

[0120]FIG. 13 is a top view of the vacuum table assembly 732 with aplatform 830 implemented as a double roller assembly. This arrangementallows two, long cylindrical shaped substrates to be rotated and platedsimultaneously. The gear 756 drives a central roller 852 through a belt850 coupled to a gear 854. This rotation allows, for example, tworeactor vessel head studs to be place side by side and rotated. Acommutator 880, such as spring-loaded roller, commutator will contacteach of the substrates, such as the reactor vessel head studs so that anelectrical signal can be provided to the substrate as desired. This alsoillustrates the versatility of the support members 804 and 802 byillustrating that various different types of platforms that may be used.

[0121]FIGS. 14a-b is a top and side view of the vacuum table assembly732 with a platform 830 implemented as a single roller assembly. It isreferred to as a single roller assembly because only one cylindricalsubstrate may be provided at a given time, unlike in FIG. 13. FIG. 14ais similar to FIG. 13 except that only two rollers are provided at eachend of the substrate as it is being rotated.

[0122]FIG. 14b is a side view similar to FIG. 12b except that theplatform 830 is implemented with the rollers on either end of asubstrate 900. The substrate 900 may be implemented as a reactor vesselhead stud to be rotated and coated. A depositant may be provided withinthe filament 820 and evaporated during the plating process.

[0123]FIGS. 15a-b is a top and side view of the vacuum table assembly732 with a platform implemented as a conductive plate 902. Referring nowto FIG. 15a, the conductive plate 902 is provided on top of the doubleroller assembly as shown and previously described in connection withFIG. 13. In a preferred embodiment, an angle iron member 920 and anangle iron member 922 are positioned across the rollers as shown. Thisprovides additional mechanical stability and support for the plate 902.

[0124]FIG. 15b shows a side view of what is illustrated in FIG. 15aexcept that a substrate 900 is shown on the surface of the conductiveplate 902. The conductive plate 902 is electrically coupled to theelectrical feed through 760 by a commutator or direct connection 880.

[0125]FIG. 16 is a side view of the configurable vacuum system 1000 withthe vacuum table assembly 732 shown resting on and transported by a cart960 to the vacuum chamber 700 so that the various connections of thevacuum table assembly 732 may be automatically connected as the vacuumtable assembly 732 is slid or rolled into the vacuum chamber 700. Acontrol cabinet 962 is shown for controlling a plating or depositantprocess and to control the mechanical and electrical inputs into thevacuum chamber 700.

[0126] Thus, it is apparent that there has been provided, in accordancewith the present invention, a configurable vacuum system and method thatsatisfies one or more of the advantages set forth above. Although thepreferred embodiment has been described in detail, it should beunderstood that various changes, substitutions, and alterations can bemade herein without departing from the scope of the present invention,even if all, one, or some of the advantages identified above are notpresent. For example, one or more of the mechanical drive, theelectrical feed through, and the filament power connector may not beneeded in a particular deposition technology application. As anotherexample, the mechanical drive and the filament power connector may, forexample, couple directly to the support from of the vacuum tableassembly, through one another, or through some intermediate coupling ormounting. The present invention may be implemented using any of avariety of materials and configurations. For example, any of a varietyof vacuum pump systems, equipment, and technology could be used in thepresent invention. These are only a few of the examples of otherarrangements or configurations of the configurable vacuum system andmethod that is contemplated and covered by the present invention.

[0127] The various components, equipment, substances, elements, andprocesses described and illustrated in the preferred embodiment asdiscrete or separate may be combined or integrated with other elementsand processes without departing from the scope of the present invention.For example, the mechanical drive and the electrical feed through couldconceivably be implemented through one structure. Other examples ofchanges, substitutions, and alterations are readily ascertainable by oneskilled in the art and could be made without departing from the spiritand scope of the present invention.

What is claimed is:
 1. A configurable vacuum system comprising: a vacuumtable assembly for use in a vacuum chamber for plating a substrate, thevacuum table assembly including: a support frame operable to providestructural support to the vacuum table assembly, a sliding meanspositioned to support the vacuum table assembly when the vacuum tableassembly is positioned in the vacuum chamber, the sliding means operableto facilitate the movement of the vacuum table assembly, an insulatedsurface with a top, a bottom, and supported by the support frame, and aplatform operable to rotate and support the substrate, the platformpositioned above the top of the insulated surface; a mechanical driveoperable to rotate the platform; an electrical feed through operable tocommunicate an electrical signal to the substrate on the platform; afilament positioned relative the substrate, the filament operable to bepositioned in more than one location so that substrates of differentshapes may be plated; and a vacuum chamber having a main opening, aninternal volume, a receiving means operable to receive and support thevacuum table assembly within the internal volume of the vacuum chamber,and wherein the sliding means of the vacuum table assembly is operableto engage the receiving means of the vacuum chamber.
 2. The configurablevacuum system of claim 1, further comprising: a cart operable to supportthe vacuum table assembly when outside of the vacuum chamber, and toassist with positioning the vacuum table assembly into the vacuumchamber and out of the vacuum chamber.
 3. The configurable vacuum systemof claim 1, wherein the sliding means of the vacuum table assembly is aroller.
 4. The configurable vacuum system of claim 1, wherein thesliding means of the vacuum table assembly is a bearing.
 5. Theconfigurable vacuum system of claim 1, wherein the sliding means of thevacuum table assembly is a low friction surface.
 6. The configurablevacuum system of claim 1, wherein the receiving means of the vacuumchamber is a rail positioned in the internal volume of the vacuumchamber, and the sliding means of the vacuum table assembly engages therail.
 7. The configurable vacuum system of claim 1, wherein the platformis a turntable.
 8. The configurable vacuum system of claim 1, whereinthe platform is a roller assembly.
 9. The configurable vacuum system ofclaim 1, wherein the platform of the vacuum table assembly is positionedabove the top of the insulated surface through a detachable coupling.10. The configurable vacuum system of claim 9, wherein the platform isone from the group that includes a turntable and a roller assembly. 11.The configurable vacuum system of claim 1, wherein the electrical feedthrough communicates an electrical signal to the substrate that includesa negative dc potential.
 12. The configurable vacuum system of claim 1,wherein the electrical feed through communicates an electrical signal tothe substrate that includes an rf signal.
 13. The configurable vacuumsystem of claim 1, wherein the electrical feed through communicates anelectrical signal to the substrate that includes a negative dc potentialand an rf signal.
 14. The configurable vacuum system of claim 1, furthercomprising: a motor operable to rotate the mechanical drive.
 15. Theconfigurable vacuum system of claim 14, wherein the motor is positionedin the vacuum chamber.
 16. The configurable vacuum system of claim 14,wherein the motor is positioned external the internal volume of thevacuum chamber.
 17. The configurable vacuum system of claim 14, whereinthe motor includes one from the group that includes an electric motor, ahydraulic motor or a manual motor.
 18. The configurable vacuum system ofclaim 1, wherein the mechanical drive is positioned in the vacuumchamber.
 19. The configurable vacuum system of claim 1, wherein themechanical drive is supported by the vacuum table assembly.
 20. Theconfigurable vacuum system of claim 1, wherein the filament is supportedby the vacuum table assembly.
 21. The configurable vacuum system ofclaim 1, wherein the filament is positioned in the vacuum chamber. 22.The configurable vacuum system of claim 1, further comprising: afilament power source operable to electrically couple to the filament toprovide power to the filament.
 23. The configurable vacuum system ofclaim 1, wherein the insulated surface of the vacuum table assemblyincludes a layer of micarta.
 24. The configurable vacuum system of claim1, wherein the insulated surface of the vacuum table assembly includesan opening, and the mechanical drive extends through the opening andcouples to the platform to provide rotation to the platform.
 25. Theconfigurable vacuum system of claim 1, wherein the platform is aturntable made of an electrically conductive material, and theelectrical feed through is operable to communicate the electrical signalto the substrate by contacting the turntable, upon which the substrateresides.
 26. The configurable vacuum system of claim 25, wherein theelectrical feed through extends through an opening in the insulatedsurface of the vacuum table assembly.
 27. The configurable vacuum systemof claim 1, wherein the platform is a roller assembly and the substrateresides on a roller of the roller assembly, and wherein the electricalfeed through is operable to communicate the electrical signal to thesubstrate by contacting the substrate through a commutator.
 28. Theconfigurable vacuum system of claim 27, wherein the electrical feedthrough extends through an opening in the insulated surface of thevacuum table assembly.
 29. A configurable vacuum table assembly for usein a vacuum chamber for plating a substrate, the configurable vacuumtable assembly comprising: a support frame operable to providestructural support to the configurable vacuum table assembly; a rollingmeans positioned to support the configurable vacuum table assembly whenthe configurable vacuum table assembly is positioned in the vacuumchamber, the rolling means operable to facilitate the movement of theconfigurable vacuum table assembly; an insulated surface with a top, abottom, and supported by the support frame; a platform that is one fromthe group that includes a turntable and a roller assembly, the platformoperable to rotate and support the substrate, the platform positionedabove the top of the insulated surface through a detachable coupling;and a filament positioned relative the substrate, the filament operableto be positioned in more than one location so that substrates ofdifferent shapes may be plated.
 30. The configurable vacuum tableassembly of claim 29, wherein the insulated surface includes an opening,and further comprising: a mechanical drive that extends through theopening in the insulated surface and couples to the platform to providerotation to the platform when rotational motion is provided to themechanical drive.
 31. The configurable vacuum table assembly of claim29, further comprising: an electrical feed through operable tocommunicate an electrical signal to the substrate on the platform whenan electrical signal is provided through the electrical feed through.